Flue-cleaner.



C. MAIER.

FLUE CLEANER.

APPLlcMmn man luNE 20.1912.

15,1 34934@ Patented Apr. 6,1915.

MITI'` meegaan T0 all 'whom 'it ma, concern Be it known t at l, CHARMES'MAIER, a

`citizen of the United States, residing at Canby, in the county ofYellow Medicine and State of Minnesota, have invented certain new anduseul Improvements in Flue- Cleaners, of which the following is especilication.

My invention relates to improvements 1n Hue cleaners designedparticularly for scraping from boiler dues the scale and accretionswhich become encrusted thereon in use, its objects being, among otherthings,

to rovide an improved scraper which can.y be Ieasily operated from theoutside of. the,

boiler without removing or loosening the dues from the due sheets, andwhich will eidectually cut the accretions freni the dues. With these andother objects in'view the invention consists in the construction,coimbination, and arrangement of parts hereinafter described andclaimed.

ln the accompanying drawingsdog part of this specification, Figure l isa front elevation of a fragment of a boiler containing the inventionwith the front uesheet partly broken away to show the llues andScrapers; Fig. 2 is a vertical section through the same on line m-mofFig. l; Fig' is'al perspective view of the improved scrapexjin placeupon a flue; Fig. d is a detail showing a fragment of the ue with one ofthe ring ngers of the scraper in longitudine section; Fig. 5 is aperspective detail of the slotted lug upon the scraper; lFig. 6 is aperspective view of the operating rod or tool, partly broken away; Fig.7 is across section through the key end of the tool on line u--Jw ofFig. 6; Fig. 8 is a perspective view of one of the threaded closures forthe tool opening in the due-sheet; and Fig. 9 is a perspective view ofone of the protective tubular plugs used in the tool opening when thescraper is being operated.

ln the drawings A and B represents the front and rear flue-sheets,respectively, of a tubular boiler, in vwhich are secured in the usualway a number of dues 2. Upon each of these flues is slidably supportedone of the Scrapers 3 which forni the subject ot the present invention.The scraper consists of a tubular shell of sheet metal having at one,and preferably both, of its ends a row of separated outwardly bowedscraping fingers t, each of which terminates in a mite 4 `hav-Spectacetton or Lettera Patentf i amusante mea rma ae, iaia amai no.roasts.

to increase their resilience.

Patenten .aan e, tera The ngers are bowed out from the due in order topress their' cutting edges elastically against the Hue and are cut awayat the sides lhe Scrapers are sprung over the lues before the dueshavebeen secured in the flue-sheets.

The front due-sheet A is formed? near each hue witha threaded hole 7through' which the tool C can be inserted to operatethe scraper. Thistool is a long rod terat.- in in a plano-convex key-end having a dat# sii 8 and a round side 9. lln the key-end is a neck l0 of reduceddiameter, eccentric to the axis ot the rod, havin on either side ashoulder l1. rlhe key-en of the rod is adapted to be inserted throughthe key hole opening 12in an earor lu 13 which prrr1 jects radially fromtheshe ot the scraper.

Gti.

tey

v dit The holes 7 in the Hue-sheet are noriinallv` closed vby'means ofthreaded plugs M, but when the rod is to be inserted through the holevthese plugs are removed, and preferably replaced by threaded tubularplugs l5, as shown in Fig. 9, which can be screwed into the holes toprotect the threads in the due-sheet from being crushed or damaged bythe tool as it is worked back and forth.

lin use the tool C is inserted through one of' the holes 7, protected,if desired, by means of a tubular protective plug l5, until its endpasses'tlirouh the slot 12. order that `it may enter 4l.,

turned to brin its convex side 9 adjacent to the scraper. t can then bethrust through the slot until its neck portion lOis lodged within it.The tool is then turned in the direction of the arrow in Fig. 7 to bringits Hat sidey 8 toward the body of the scraper.

In this position the neck l0 will be thrown e slot the tool must orother matter that maybe encrusted on the outside of the fiue.

By having the fingers separated from one another, an outwardly bowed,the scraper can be sprung over ilues of different sizes, and the knifeedges will always rest elastically against the flue. As shown in thedrawings these knives are preferably curved to conform to the flue anextended transversely to form a practically continuousA cutting edge.'

It will be understood that the structure here shown and described isonly the preferred embodimentof the invention, and that the same can bemodified in various ways without departing from the` princi le of theinvention, the scope of which is e'- fined in the claims.

I claim as my invention: v

1. A flue cleaner comprising a. tubular shell adapted to fit slidinglyover a iiue and having outwardly bowedspring fingers teri minating incontiguous knives encircling the flue and conforming to the curvaturethereof.

2. The combination Vwith a tubular shell adapted to vfit slidn ly abouta flue, said shell having termina spring knives and a radial lug ormedwith av ke -hole slot, of an operating rod formed with a key-endcoacting with saidslot to lock the rod to the shell, whereby to movethesame endwi se.

3. A flue cleaner comprising a tube Lof resilient sheet metal having arigid -tubular middle portion, and being horizontall slit andtransversely bowed on eachside o said middle portion to form mutuallyindependent barrel-shaped sprin scraping fingers.

In testimon whereo I ax my signature in presence o two witnesses.

CHARLES MAIER.

Witnesses: y

H. SMITH,

. Annina P. Lo'rmor.

